The growing subfield of infant and early childhood temperament holds great promise for conceptualizing the individual's contribution to social and cognitive development; however, the field is handicapped by insufficient basic psychometric research and inadequately standardized and validated measurement instruments. The goal of this research is to construct and validate a novel, theoretically based method for measuring temperament-related behavior: The Laboratory Temperament Assessment Battery (LAB-TAB). Building on extensive pilot work supported by the Foundation for Child Development, LAB-TAB will yield scores for activity, fear, anger, pleasure, and interest. Each of these dimensions will be objectively scored from standardized laboratory procedures. Embedded within the construction of LAB-TAB are three validity studies that examine developmental continuity, cross-method covergence, and relations between facial expressions and overt behavioral responses. The health relatedness of the research derives from the proposition that early temperament is implicated in the etiology of various childhood behavioral problems. Successful implementation of LAB-TAB should improve understanding of factors within the child that either contribute to vulnerability or protect the child from stressful environmental influences.